Main Emission Research Articles

GHG emission quantification and reduction pathway of subway shield tunnel engineering: a case study on Guangzhou Metro, China.

The shield method is a commonly used construction technique in subway tunnel engineering. However, studies on greenhouse gas (GHG) emissions specifically in subway shield tunnel engineering are lacking. This study aims to investigate the GHG emission characteristics and GHG reduction pathways during the construction period of subway shield tunnels. Firstly, based on the life cycle assessment (LCA) method, a greenhouse gas (GHG) emission quantification model for the shield tunnel construction period was developed using a multi-level decomposition of construction. Then, the GHG emission level and intensity during the construction period of a case project are quantified, and its emission characteristics and GHG reduction potential points are assessed. Finally, a comprehensive path for GHG reduction in subway shield tunnel engineering is proposed. The research results indicate that constructing 1 km of subway shield tunnel can generate 19,294.28 t CO2eq. Among these, material production element dominates the emissions with a percentage of 89.05%, while transportation and mechanical construction elements contribute 1.81% and 9.14%, respectively. From the structure perspective, the main structure contributes 88.73% of total emissions, while the ancillary structure contributes 11.27%. Among them, the working shaft and tunnel segments are the main sources of emissions for the main structure, accounting for 23.65% and 65.08%, respectively. Connecting channel and end reinforcement are the main emission sources of the ancillary structures, accounting for 43.63% and 31.30%, respectively. These findings provide a scientific foundation for the environmentally friendly transformation of urban railway development regarding pursuing "carbon peaking and carbon neutrality" strategic goals.

Increase the inversion degree in Er-doped MgGa2O4 spinel nanofilms to obtain strong electroluminescence

The Ga2O3/MgO/Er2O3 nanolaminates are fabricated by atomic layer deposition and crystallized into Er-doped MgGa2O4 spinel (MGS:Er) nanofilms after annealing, with their electroluminescence (EL) performance characterized. The annealing above 600 °C achieves the polycrystalline spinel nanofilm, and the crystallization is promoted by the higher annealing temperature and Ga2O3/MgO ratio. The dopant Er3+ ions preferably substitute into the octahedron sites occupied by Ga3+ ions in ordinary spinel and Mg2+ in anti-spinel lattice, while the inversion degree is confirmed to increase with the reduction of Ga2O3/MgO ratio and annealing temperature, resulting the relatively enhanced secondary EL at 1542 nm. This perturbation by Er3+-substitution into anti-spinel sites improves the emission intensity and excitation efficiencies, the main EL emission peaking at 1531 nm from the optimal MGS:Er device exhibits the excitation efficiency reaching 5.8 %, with the enhanced electrical injection realizing the maximum EL intensity above 17.3 mW/cm2. The fluorescence lifetime of these MGS:Er devices is established in the range of 371–760 μs, which decreases mainly with the Er concentrations. The prototype device using the near-stoichiometric Ga2O3/MgO ratio shows the operation time of 1.12 × 105 s. This work explores the fabrication of Si-based spinel nanofilms with designed composition and special microstructure, and their practical application in optoelectronics.

Effect of magnetospheric conditions on the morphology of Jupiter’s ultraviolet main auroral emission as observed by Juno-UVS

Auroral emissions are a reflection of magnetospheric processes, and at Jupiter, it is not entirely certain how the morphology of the UV main emission (ME) varies with magnetospheric compression or the strength of the central current sheet. This work leverages the observations from Juno-UVS to link ME variability with particular magnetospheric states. We employed novel arc-detection techniques to determine new reference ovals for the ME from perijoves 1 through 54, in both hemispheres, and analysed how the size and shape of the ME vary compared to this reference oval. The morphology and brightness of the ME vary in local time: the dawn-side ME is typically expanded, while the dusk-side ME is contracted, compared to the reference oval, and the dusk-side ME is twice as bright as the dawn-side ME. Both the northern and southern ME and the day-side and night-side ME expand and contract from their reference ovals synchronously, which indicates that the variable size of the ME is caused by a process occurring throughout the Jovian magnetosphere. The poleward latitudinal shift of the auroral footprint of Ganymede correlates with the poleward motion of the ME, whereas a similar relation is not present for the footprint of Io. Additionally, the expansion of the ME correlates well with an increase in magnetodisc current. These two results suggest that a changing current-sheet magnetic field is partially responsible for the variable size of the ME. Finally, magnetospheric compression is linked to a global ME contraction and brightening, though this brightening occurs predominantly in the day-side ME. This observation, and the observation that the dusk-side ME is typically brighter than the dawn-side ME, stands in contrast to the modelled and observed behaviour of field-aligned currents and thus weakens the theoretical link between field-aligned currents and the generation of the auroral ME.

Effect of multiple injection optimization on combustion characteristics of low-pressure EGR system engine

Abstract In recent years, reducing oil consumption and pollutant discharge in transportation industry has become an important measure to alleviate energy crisis and environmental pollution. Therefore, the fuel economy and emission characteristics of the engine have become an important index to evaluate the quality of an engine, so EGR technology has gradually become the standard of gasoline engines. But EGR is not always good. In order to alleviate the adverse effects of EGR on combustion, further research on engine combustion is needed. In order to study the effect of multiple injection strategy on engine combustion characteristics, this paper takes a high pressure direct injection gasoline engine equipped with low pressure EGR system as the research object, and verifies the designed multiple injection strategy on special test equipment. A large amount of combustion data of the engine under the same load, different fuel injection stages and fuel injection ratios were collected. By comparing the evaluation indexes of main pollutant emission, fuel consumption and combustion stability, it is found that with the increase of injection times, the combustion characteristics and knock of the engine show a trend of improvement. After using multiple injection strategies at 2000r/min, it can be seen that the optimized injection strategy has better emission characteristics and lower fuel consumption lower knock intensity than that before the injection mode optimization without affecting the power performance.

Application of hydrostatic local thermodynamic equilibrium atmosphere models to interpretations of supersoft X-ray source spectra

Supersoft X-ray sources (SSSs) are accreting white dwarfs (WDs) with stable or recurrent thermonuclear burning on their surfaces. High-resolution X-ray spectra of such objects are rather complex, often consist of several components, and are difficult to interpret accurately. The main emission source is the hot surface of the WD and the emergent radiation can potentially be described by hot WD model atmospheres. We present a new set of such model atmosphere spectra computed in the effective temperature range from 100 kK to 1000 kK, for eight values of surface gravity and three different chemical compositions. These compositions correspond to the solar one as well as to the Large and Small Magellanic Clouds, with decreased heavy element abundances, at one-half and one-tenth of the solar value. The presented model grid covers a broad range of physical parameters and, thus, it can be applied to a wide range of objects. It is also publicly available in XSPEC format. As an illustration, we applied it here for the interpretation of Chandra and XMM grating spectra of two classical SSSs, namely, CAL 83 (RX J0543.5–6823) and RX J0513.9–6951. The obtained effective temperatures and surface gravities of Teff ≈ 560 kK, log g ≈ 8.6–8.7, and Teff ≈ 630 kK, log g ≈ 8.5–8.6, respectively, are in a good agreement with previous estimations for both sources. The derived WD mass estimations are within 1.1–1.4 M⊙ for CAL 83 and 1.15–1.4 M⊙ for RX J0513.9–6951. The mass of the WD in CAL 83 is consistent with the mass predicted from the respective model of recurrent thermonuclear burning.

Variation Characteristics and Source Analysis of Atmospheric Ozone Pollution in Guanzhong Region

Guanzhong urban agglomeration has a good development foundation and great development potential, and it has a unique strategic position in the national all-round opening up pattern. In recent years, the problem of near-surface ozone （O3） in the Guanzhong Region has become increasingly prominent, which has become a bottleneck affecting the continuous improvement of air quality. In order to effectively prevent and control O3 pollution, this study analyzed the characteristics of annual, monthly, and daily changes in O3 concentration in the Guanzhong Region based on the environmental monitoring data from 2018 to 2021. A geo-detector was used to study the driving factors of the spatial differentiation of O3 concentration, and the sources of O3 were analyzed using a backward trajectory model and emission inventory construction. The results showed that the daily and monthly variation in O3 concentration in the Guanzhong Region were unimodal. The daily maximum value appeared at 15：00, the minimum value appeared at 07：00, the peak value of the monthly average appeared in June, and the valley value appeared in December. The O3 concentration was highest in summer, followed by that in spring, and the lowest in winter. The days of O3 exceeding the standard showed mainly mild pollution, and moderate and above pollution showed a trend of decreasing first and then increasing. The O3 concentration in the Guanzhong Region was mainly closely related to precursors and meteorological factors, and the explanatory power of the interaction of each factor was significantly greater than that of any single factor. The regional transport of O3 concentration in the Guanzhong Region was mainly affected by easterly airflow, followed by the northwest direction, with the potential source areas located mainly in Henan Province and Hubei Province. The main local sources of volatile organic compounds （VOCs） were solvent use sources, process sources, and mobile sources, and the main emission sources of nitrogen oxides （NOx） were mobile sources and industrial production combustion sources. The research results have a guiding significance for O3 joint prevention and control in the Guanzhong Region.

Multi-scale thermal degradation of wood pellets under low heating rates: Experiments and modeling

Pyrolysis and combustion experiments were carried out on a single wood pellet in a drop tube furnace, under a heating rate of 5 °C/min. Kinetic modeling was done using the Extended Independent Parallel Reaction model. Three reactions were considered in the pyrolysis case and only one in the combustion case. In the pyrolysis case, a thermal model was proposed which is coupled with the kinetic model to correct the temperature inside the pellet. In the combustion case, the mass rate curve was compared to that of the main gaseous emissions. The mass and mass rate curves between the combustions of a pellet in the drop tube furnace and of pellet sawdust in a thermobalance under the same heating rate were compared.

Distinguishing the effects of lattice Gd3+ and segregated Gd3+ on optical properties of Yb:GdYAG transparent ceramics

Whether adding Gd3+ in Yb:GdYAG broadens absorption and emission peaks for better laser performance is recently under debate. By preparing (Yb0.05Y0.95-xGdx)3Al5O12 (x = 0.2, 0.6, 1, 5, 10, 20 at%) transparent ceramics with one-step solid-state reactive sintering under vacuum, we report a non-monotonic relation between increasing Gd3+ content and micro-structure/properties. Specifically, the grain size decreases till x = 10 at%, but increases at 20 at% with secondary phases formed at grain boundaries by segregated Gd3+. The optimal optical properties are achieved at 10 at%. The in-line transmittance reaches 83.9 % at 1100 nm. Absorption and emission cross-sections are significantly broadened (8.0 × 10−21 cm2 at 940 nm and 26.7 × 10−21 cm2 at 1030 nm, respectively). The FWHM of main emission peak at 1030 nm receives a ∼60 % extension to 15.2±0.4 nm. It indicates lattice Gd3+ broadens peak widths and improves transparency, while segregated Gd3+ diminishes peak broadening and adversely affects transparency.

Temperature-dependent law of transition probability associated with main emission states in YVO4:Re3+ (Re3+=Sm3+, Dy3+ and Eu3+)

The understanding of how radiative transition probabilities change with temperature is crucial for comprehending the relationship between fluorescence behavior and temperature. However, although various models have been proposed to explain the patterns of transition probabilities (A) with temperature changes, they lack consistency due to their derivation from distinct microscopic perspectives. In this study, the macroscopic law of the temperature-dependent A for the 4G5/2, 4F9/2, and 5D0 energy states in YVO4:Re3+(Re3+=Sm3+, Dy3+ and Eu3+) was obtained. Three rare earth ions (Re3+) were identified for each with unique energy level properties conducive to validating the general rules of A. These ions share a common characteristic: in the visible spectrum, their main emissions originate from the radiative transitions from the same higher energy level (4G5/2 in Sm3+, 4F9/2 in Dy3+, and 5D0 in Eu3+) to lower energy levels, respectively. The A of the main emission levels, varying with T, were obtained by fitting the fluorescence decay curves. The exponential law governing non-radiative transitions was revealed after separating the radiative transition rate (WR) from A. The macroscopic law of temperature-dependent transition probabilities of 4G5/2, 4F9/2, and 5D0 energy states in YVO4:Ln3+ (Ln3+ = Sm3+, Dy3+ and Eu3+) has been found to follow the Boltzmann distribution. The results indicate that the non-radiative transitions of the main emission levels of the rare-earth ions are processes from the excited state to adjacent lower energy levels. This macroscopic pattern may serve as a foundational rule for understanding the impact of microscopic factors on A.

Spectral features of pristine and irradiated white emitting InGaN LEDs with quantum wells

The emission spectra of InGaN/GaN white light emitting diodes (WLEDs) were measured. The main emission components were a LED blue line with λmax = 443 nm and a wide double band in the range of 500…650 nm of the secondary emission of AIT-YAG phosphor (Ce). The observed non-monotonic temperature dependence of the emission was attributed to the electric-field screening effect by mobile carriers as well as to thermal quenching due to the increased density of the phonon gas. The power conversion factor of phosphor emission increased in the temperature range of 200…290 K. The total energy losses for the Stokes shift were 82% and 77% for the first (blue) and the second band, respectively. The decrement of emission at high injection currents (over 20 mA) was attributed to ballistic transfer of carriers above the quantum wells and subsequent non-radiative recombination in the barrier layers. The existence of long-term relaxation processes in the white LEDs was assumed to be due to the accumulation of In atoms. Electron beam irradiation caused WLED efficiency degradation due to the introduction of deep traps in the quantum well region. The radiation resistance of the AIT-YAG phosphor was ~1.6 times higher than that of the InGaN part.

Rapid and efficient mineralization of methylene blue dye (above 95 % in 20 min) catalyzed by ZnO nanoparticles under sunlight

This novel communication reports rapid mineralization of methylene blue dye, reaching above 95% in 20 min under cloudy sunlight catalyzed by ZnO nanoparticles, which were synthesized from N-Dipentene as a reducing agent, at different zinc acetate concentrations from 0.1 M to 0.4 M. The synthesized ZnO nanoparticles structural, morphological, compositional, and optical characterizations were done using X-ray diffraction (XRD), high resolution scanning microscopy (HRSEM), energy dispersive spectroscopy (EDS) and photoluminescence (PL) respectively. From these characterizations ZnO wurtzite crystalline structure, average crystallite size (18–25 nm) with heterogeneous elongated nanoparticles mixed to triangle like particles and low content of byproducts as well as the presence of oxygen Vacancies transitions at the red-orange bands, which contributes to the PL main emission related to the visible region at the electromagnetic spectrum were obtained, these results were correlated to the photocatalytic activity. Meanwhile direct sunlight photocatalyst using 17 mg of ZnO for 10 ppm of methylene blue dye (MB) degradation was performed, the efficiency was analyzed by Fourier transform infrared spectroscopy (FT-IR) and UV–Vis spectroscopy, obtaining the kinetic adsorption ratio fitted to the pseudo second order (PSO) and the pseudo first order (PFO) to determine the mechanism that governs this process. All those analyses were correlated to the material characteristics and synthesis concentration. A 95.38 % efficiency was reached at 20 min for the champion sample D3R followed by D4R, D2R and D1R reaching an 89.19, 80.40 and 66.86 % for the same time. The maximum mineralization efficiency for D3RA was 98.08 % at 30 min, albeit it was observed that the adsorption kinetics obeys the Pseudo second order (PSO) for D3R, D4R and D2R meanwhile for D1R is governed by the Pseudo First Order mechanism (PFO), mainly by the diffusive chemical mechanism.

Floodplain carbon dioxide emissions strongly exceed those of the main river stem: A case study of the Ob River, western Siberia

The importance of floodplains in carbon (C) evasion from the lotic systems is especially important in continental plains of low runoff such as the organic-rich Western Siberian Lowland (WSL). To quantify the relative importance of the floodplain compared to main stem CO2 emissions, we monitored a large region of the Ob River’s middle course (permafrost-free zone) over 3 months from spring to summer. We calculated seasonal water coverage using remote sensing, GIS and hydrologically-based approaches and measured CO2 emissions using floating chambers. There was a strongly pronounced seasonality in the water area’s extent of the floodplain with water covering > 40 % of land during the ∼ 30 days of the most intensive spring flood (May – June) and subsequently declining to ≤ 10 % during summer (July-August). Maximal CO2 emissions were recorded in most shallow water bodies of the floodplain, notably in temporary flooded fens and birch forests. The CO2 emissions during the study period ranged from 0.2 ± 0.2 to 0.9 ± 0.2 g Cm−2 d-1 for the floodplain and 0.03 ± 0.34 g C m−2 d-1 for the Ob’s main channel.CO2 emissions from the floodplain were ∼ 163 ± 20 t C per km for the river’s main stem during the 95 day study period. The partial contributions of temporary flooded zones, main stem, and permanent lakes / secondary channels to total emissions (1820 km² area) were 70, 16, and 14 %, respectively. Over spring and summer seasons, contributions from flooded zones ranged from 43 to 99 % of total CO2 emissions from water surfaces of the Ob River’s middle course. Extrapolation of obtained results to the entire territory of the Ob River floodplain indicates that not accounting for the floodplain emissions may sizably—up to an order of magnitude—underestimate the CO2 emissions from riverine systems in Western Siberia during open water period. Future work on the Ob River floodplain in the permafrost-bearing zone should be prioritized and would allow adequate upscaling of C emission from this environmentally important territory.

Effects of secondary air on the emission characteristics of ammonia–hydrogen co-firing flames with LES-FGM method

Ammonia, being a carbon-free fuel, is garnering increasing attention in the combustion community. However, its application is still impeded by its limited stability range and significantly NOx emissions. This study delves into the impact of primary and overall equivalence ratios (ϕpri and ϕovr) on emissions production in ammonia–hydrogen co-firing flames, utilizing a two-stage swirling model gas turbine combustor. The emissions concentration is measured using Fourier Transform Infrared Spectroscopy (FTIR). The physical and chemical processes influencing emissions production are comprehensively analyzed through a combination of Large Eddy Simulation (LES) and Flamelet-Generated Manifold (FGM) method. The reliability of the simulation is validated by the experimental data, showing a good capability in predicting the combustion. Results indicate that the two-stage combustion strategy exhibits significantly controlling effects on NOx and unburned NH3 emission. The NO emission exhibits a non-monotonic variation with ϕpri, reaching its lowest value at ϕpri≈ 1.2. Further analysis shows that ϕpri plays a crucial role in determining the temperature and OH concentration in the primary combustion zone, thereby influencing NOx production in this area. When the primary zone is operated at lean condition, the reduction on NO in secondary zone is primarily attributed to dilution effect by the secondary air. In contrast, when ϕpri> 1, the concentrations of the main emissions in secondary zone are dominated by chemical effects. In this scenario, unburned NH3 and H2 from the primary zone are consumed, resulting in a substantial production of NO in the secondary combustion zone. Additionally, with an increase in ϕpri, the secondary NO production also increases. The ϕovr exhibits two considerable effects. On one hand, an increase in ϕovr results in a higher local equivalence ratio in the secondary zone, thereby promoting local NOx production. Simultaneously, the elevated flame temperature enhances the consumption of N2O. On the other hand, the rise in ϕovr results in a reduction in vortex scale and residence time in the secondary combustion zone, leading to a decrease in local NO production.

A colorimetric/down-conversion fluorescence dual-readout probe for the recognition of Cu2+ and its application in environmental water by single PEI@NaYF4: Eu3+ nanoparticles

The pollution caused by heavy metals like Cu2+ remains a pressing issue, as the release of Cu2+-laden sewage can lead to detrimental effects on both soil ecosystems and human well-being. Herein, a novel colorimetric and down-conversion fluorescence probe, i.e. PEI@NaYF4: Eu3+ NPs, for selective and sensitive detection of Cu2+ with colorimetric and down-conversion fluorescence dual signal changes was reported. Such dual-signal detection mode offers enhanced sensitivity, accuracy, and cost-effectiveness in detecting Cu2+. The probe with spherical shape and excellent monodispersity was synthesized by a high temperature reflux method. The PEI moiety of the NPs is chosen due to the ability to chelate Cu2+ forming copper amine complexes. Such a unique feature is invoked to develop a versatile detection platform for the colorimetric detection of Cu2+ ions. In the presence of Cu2+, the visual color of probe in solution changes from colorless to blue with a low detection limit of 100 nM without any assistance of equipment. The probe emits down-conversion fluorescence with two main typical emission peaks centered at 592 and 614 nm under an excitation of 394 nm. The copper amine complexes formed by the combination of Cu2+ and the PEI moiety of the NPs quench down-conversion fluorescence by an internal filtration effect. Probe shows a specific on–off response to Cu2+ in aqueous solution with nanomolar LOD, fast response, and good selectivity, and without interference by a range of metal ions. A practical application shows that PEI@NaYF4: Eu3+ NPs have good recovery ranges of 96–105 % for Cu2+ detection in real environment water samples from different locations. This strategy proves that a colorimetric and down-conversion fluorescence probe is a potential tool for addressing heavy metal ions-induced water pollution.

Promoting low-carbon land use: from theory to practical application through exploring new methods

Cities are main carbon emissions generators. Land use changes can not only affect terrestrial ecosystems carbon, but also anthropogenic carbon emissions. However, carbon monitoring at a spatial level is still coarse, and low-carbon land use encounters the challenge of being unable to adjust at the patch scale. This study addresses these limitations by using land-use data and various auxiliary data to explore new methods. The approach involves developing a high-resolution carbon monitoring model and investigating a patch-scale low-carbon land use model by integrating high carbon sink/source images with the Future Land Use Simulation model. Between 2000 and 2020, the results reveal an increasing trend in both carbon emissions and carbon sinks in the Shangyu district. Carbon sinks can only offset approximately 3% of the total carbon emissions. Spatially, the north exhibits net carbon emissions, while the southern region functions more as a carbon sink. A total of 14.5% of the total land area witnessed a change in land-use type, with the transfer-out of cropland constituting the largest area at 96.44 km2, accounting for 50% of the total transferred area. Land-use transfer resulted in an annual increase of 77.72 × 104 t in carbon emissions between 2000 and 2020. Through land-use structure optimisation, carbon emissions are projected to increase by only 7154 t C/year from 2000 to 2030, significantly lower than the amount between 2000 and 2020. Further low-carbon land optimisation at the patch scale can enhance the carbon sink by 129.59 t C/year. The conclusion drawn is that there is considerable potential to reduce carbon emissions through land use control. The new methods developed in our study can effectively contribute to high-resolution carbon monitoring in spatial contexts and support low-carbon land use, promoting the application of low-carbon land use from theory to practice. This will provide technological guidance for land use planning, city planning, and so forth.

Open Data and Smart Tourism Development in Viticultural Areas in Serbia

Abstract Viticulture and wine production have a long tradition and are a very important agricultural branch in Serbia with a potential that is still untapped. However, the development of viticulture had different periods and stages of development, from stagnation and war events, bad climatic and economic conditions to the placement and sale of wine on the domestic and world markets. Open data enables the management of tourist destinations, but in Serbia there are no or rare examples of good practice, studies and research on this matter. Smart tourist destinations make up the concept of tourist development, the basis of which lies in innovative solutions and modern technology. Numerous tourist destinations in Serbia is not even at the beginning of improving smart tourism in destinations or are just beginning to implement them. The Belgrade viticultural region has a high rating due to its proximity to the destination itself, primarily Belgrade, as the main and important emissions center, which makes the trip shorter, the longer stay and the participation of tourists more attractive. The capital of the Republic of Serbia is located in this region, as well as the immediate surroundings of other city centers with a large share of the population. Belgrade is the main transit point of Serbia: good traffic connections, as well as the proximity of the "Nikola Tesla" Airport. In the vineyards of Serbia, the formation of wine products and accompanying tourist content did not occur, but they remained in the tourist offer as part of the rural tourist offer.

Estimating the Carbon Footprint of Healthcare in the Canton of Geneva and Reduction Scenarios for 2030 and 2040.

Switzerland, a wealthy country, has a cutting-edge healthcare system, yet per capita, it emits over one ton of CO2, ranking among the world's most polluting healthcare systems. To estimate the carbon footprint of the healthcare system of Geneva's canton, we collected raw data on the activities of its stakeholders. Our analysis shows that when excluding medicines and medical devices, hospitals are the main greenhouse gas emitter by far, accounting for 48% of the healthcare system's emission, followed by nursing homes (20%), private practice (18%), medical analysis laboratories (7%), dispensing pharmacies (4%), the homecare institution (3%), and the ambulance services (<1%). The most prominent emission items globally are medicines and medical devices by far, accounting for 59%, followed by building operation (19%), transport (11%), and catering (4%), among others. To actively reduce Geneva's healthcare carbon emissions, we propose direct and indirect measures, either with an immediate impact or implementing systemic changes concerning medicine prescription, building heating and cooling, low-carbon means of transport, less meaty diets, and health prevention. This study, the first of its kind in Switzerland, deciphers where most of the greenhouse gas emissions arise and proposes action levers to pave the way for ambitious emission reduction policies. We also invite health authorities to engage pharmaceutical and medical suppliers in addressing their own responsibilities, notably through the adaptation of procurement processes and requirements.

Measurements of the absolute gamma-ray emission intensities from the decay of 166Ho

166Ho (T1/2≈ 26.8 h) is an emerging theragnostic radionuclide of interest in nuclear medicine due to its peculiar decay scheme, featuring high-energy β− emission (≈ 1.8 MeV) coupled with the main gamma-ray emission (≈ 80.6 keV). Using the new 166Ho activity standard and the well-calibrated, high-energy resolution HPGe detector, both available at ENEA-INMRI, a new determination of several 166Ho gamma-ray emission intensities, Iγ, was performed with low uncertainty. The new Iγ values contributed to the Decay Data Evaluation Project.

Realizing low-carbon development of industrial parks in China: Model construction and its application

As the main energy consumption and emission area, carbon emission reduction for industrial parks is a pivotal target for China. In this study, a multi-objective optimization model was established to quantitatively develop low-carbon development strategies for industrial parks that simultaneously considers land productivity, energy structure and efficiency, carbon emissions, and industrial structure optimization. A Monte Carlo method was adopted to investigate the uncertainties associated with emission-reduction technologies and economic development. A study on an industrial park showed that with the implementation of a series of fossil energy-saving measures, the percentage of clean energy in the park is projected to reach 62.6–72.2 %, while the percentage of output from energy-intensive enterprises relative to the total output of the industrial park decreases from 3.78 % in the baseline year to 1.74–3.29 %, and carbon emissions are projected to decrease by 69–85.4 % relative to the benchmarking scenario. This implies that the model developed in this study is effective and can serve as a roadmap for designing industrial parks to realize low-carbon development.

Intrinsic Emission of PSR B1937+21 at 327 MHz

At 327 MHz, the observed emission of PSR B1937+21 is greatly affected by scattering in the interstellar medium, on a timescale of order the pulse period. We use the bright impulsive giant pulses emitted by the pulsar to measure the impulse response of the interstellar medium and then recover the intrinsic emission of the pulsar by deconvolution—revealing fine structure on timescales not normally observable. We find that the intrinsic widths of the main pulse and interpulse in the pulse profile are similar to those measured at higher frequencies. We detect 60,270 giant pulses, which typically appear as narrow, ∼100 ns bursts consisting of one to a few nanoshots with widths ≲ 10 ns. However, about 10% of the giant pulses exhibit multiple bursts that seem to be causally related to each other. We also report the first detection of giant micropulses in PSR B1937+21, primarily associated with the regular main pulse emission. These are distinct from giant pulses not only in the phases at which they occur, but also in their larger widths, of order a microsecond, and steeper energy distribution. These measurements place useful observational constraints on emission mechanisms for giant pulses as well as the regular radio emission of millisecond pulsars.